Welcome to the Homepage of INTES GmbH, Stuttgart

If this webpage is presented to you in a simple layout, you are probably using an old browser (e.g. Netscape 4.78) without sufficient CSS-support. In order to be able to utilize this website in full extent, please use a modern browser.

[ PERMAS > Applications ]            Sitemap | Contact | Imprint

Engine Analysis with PERMAS

Many physical effects play an important role during a mechanical analysis of combustion engines. In static analysis such effects are leak tightness and durability under changing temperature conditions and in dynamic analysis there are sound radiation and frequency responses of complex engine assemblies. At least in static analysis the influence of temperature requires a coupled analysis taking heat transfer into account. Modeling the mounting of an engine requires the consideration of bolt loading conditions where the correct sequence of bolt pre-stressing and operating loads is of major importance. In addition, nonlinear material behavior has to be considered. These and other effects are important for engine analysis.

Heat Transfer

Applications are e.g. the analysis of operating temperatures and the aging in an oil bath by simulating the cooling down process. The following features are available:

  • Nonlinear material behavior with temperature-dependent conductivity and heat capacity,
  • Temperature-dependent heat convection for the modeling of heat exchange with the surrounding,
  • Automatic solution method for nonlinear heat transfer with automatic step control and several convergence criteria, i.e. an automatic load stepping for steady-state analyses and an automatic time stepping for transient analyses,
  • Convenient and very detailed specification possible for loading steps and points in time where results have to be obtained,
  • Full coupling to subsequent static analysis (steady-state and transient),
  • Heat exchange by radiation can be included, if this makes a relevant effect on the temperature field.
  • Bolt Pretension with pitch and flank angle


Static deformations are calculated under various loads with linear and nonlinear material behavior:

  • Nonlinear material models:
    • plastic deformation,
    • nonlinear elastic,
    • creep,
    • cast iron with different material behavior under tension and compression.
  • Gasket elements:
    • for convenient simulation of sealings,
    • the behavior of sealings is described by measured pressure-closure curves,
    • input of many unloading curves possible.
  • Contact analysis:
    • many contacts possible (> 30,000),
    • unrivaled short run times,
    • most advanced solver technology,
    • friction can be taken into account with transitions between sticking and sliding,
    • bolt conditions can be applied in one step,
    • specification of a realistic loading history,
    • contact results: contact pressure, contact status, contact forces, saturation, etc.
  • Submodeling:
    • for subsequent local mesh refinements,
    • automatic interpolation of displacements to get kinematic boundary conditions for a finer mesh,
    • then, a local analysis is performed e.g. to achieve more accurate stresses.
valve train
Static analysis of valve train with large rotation

High performance

Due to typically large models in engine analysis all analysis methods are oriented towards highest possible performance. The following points can be highlighted:

  • outstanding performance through special algorithms for large models with nonlinear material and contact,
  • contact algorithms have been strictly designed to meet the needs of large models with many contacts,
  • unrivaled fast method for linear material and contact.


By using the same software for dynamic and static simulations only one structural model is necessary. All dynamic methods are available for engine analysis. Some important points are:

  • Eigenvalues and mode shapes for large solid models can be calculated using MLDR.
  • Fast dynamic condensation methods support the efficient analysis of engines with many attached parts.
  • By using dry condensation even fluids can be integrated in a dynamic model without taking along pressure degrees of freedom (e.g. in an oil pan).
  • Calculation of sound particle velocity is supported for the evaluation of noise emission of engines.